Chapter 11.6, Problem 4LC

To determine

Do the data in the table represent a direct variation or an inverse variation? Write an equation that models the data.

Answer to Problem 4LC

Direct variation, $-2x=y$

Explanation of Solution

Given information:

x	y
-3	6
-6	12
-9	18

Calculation:

The above data represent a direct variation because the value of x and y both directly depends on each other.

For the given table the equation will be

  $\begin{array}{c}-2x=y\\ puttingx=-3andy=6\\ -2\cdot \left(-3\right)=6\\ 6=6\\ puttingx=-6andy=12\\ -2\cdot \left(-6\right)=12\\ 12=12\\ puttingx=-9andy=18\\ -2\cdot \left(-9\right)=18\\ 18=18\end{array}$

all the data in the table satisfies the equation $-2x=y$.